Interpretive Summary: Rangeland management could benefit from east-to-use and accurate ecosystem models to assist in enterprise-level decision making, but efforts to date have had limited effectiveness. Reasons for this include: 1) current models often fail to address contemporary needs associated with management of rangelands for multiple ecosystem goods and services, 2) spatial and temporal variability and inherent climatic variability are often not included in scenario forecasting, risk assessments and implementing adaptive management, and 3) integrating experimental and experiential knowledge and observations into decision making has rarely been incorporated. For land managers, models could be linked with predictive forecasting of precipitation in real-time via web accessible portals for spatially explicit forage projections that guide stocking decisions for adaptive management. Increasing the utility of models for land managers will be achieved less by further technical advances and model complexity and more by the integration of experimental and experiential knowledge and observations into frameworks that facilitate outcome-based decision making. One promising framework is the ecological site description which incorporates state-and-transition models that utilize both experimental and experiential knowledge for decision making.

Technical Abstract:
A tremendous need exists for ecosystem models to assist in rangeland management, but the utility of models developed to date has been minimal for enterprise-level decision making. Three areas in which models have had limited effectiveness for land managers are 1) addressing contemporary needs associated with management of rangelands for multiple ecosystem goods and services, 2) coping with spatiotemporal and climatic variability in scenario forecasting, risk assessments and implementing adaptive management, and 3) integrating experimental and experiential knowledge and observations into decision making. Utility of models for decision making could be improved by incorporating 1) fundamental understanding of the historic drivers (e.g., grazing, fire) and spatiotemporal variation in their effects on multiple ecosystem functions, 2) manager capacity including experience, skills and availability, and 3) changing constraints of the enterprise (e.g., ranch) which commonly pertain to economics. Fundamental knowledge of variability, directionality, magnitude and uncertainty of climate change should also be addressed in models to enhance adaptive management. For example, models could be linked with predictive forecasting of precipitation in real-time via web accessible portals for spatially explicit forage projections that guide stocking decisions for adaptive management. Increasing the utility of models for land managers will be achieved less by further technical advances and model complexity and more by the integration of experimental and experiential knowledge and observations into frameworks that facilitate outcome-based decision making. One promising framework is the ecological site description which incorporates state-and-transition models that utilize both experimental and experiential knowledge for decision making.